/*
 * @Author: your name
 * @Date: 2021-04-14 08:05:02
 * @LastEditTime: 2021-04-15 07:52:58
 * @LastEditors: Please set LastEditors
 * @Description: In User Settings Edit
 * @FilePath: \学习笔记\C语言\技能1.c
 */
// 练习题
#include "studio.h"
int main()
{
    // 大写英文转小写
    char ch;
    scanf("%c", &ch);
    ch = (ch > 'A' && ch <= 'Z') ? (ch + 32) : ch;
    printf("%cn", ch);
    return 0;

    // 长度测试运算符
    //sizeof
    char a[100] = "hello";
    sizeof(a);
    strlen(a);

    // 混合运算
    int a2;
    float t;
    a2 = 15;
    t = (float)a2 / 30;
    printf("a=%d\n", a2);
    printf("t=%f\n", t);
}
#include "studio.h"
int main()
{
    //
    int F;
    float C;
    scanf("%c", &F);
    C = 5 * (F - 32) / 9.0;
    printf("%f", C);
    return 0;
}

#include "studio.h"
int main()
{
    int r;
    float s;
    float c;
    float v;
    float m;
    scanf("%c", &r);
    s = 3.14 * r * r;
    c = 3.14 * r * 2;
    v = 4 / 3 * 3.14 * r * r * r;
    m = 4 * 3.14 * r * r;
    printf("面积=%f\n", s);
    printf("周长=%f\n", r);
    printf("面积=%f\n", v);
    printf("表面积=%f\n", m);
    return 0;
}

#include "studio.h"
int main()
{
    int t, b, h;
    scanf("%c", $t);
    scanf("%c", $b);
    scanf("%c", $h);
    float s;
    s = (t + b) * h / 2.0;
    printf("%f", s);
}

#include "studio.h"
int main()
{
    // 输入三角形的三条边,计算该三角形面积
    int l1, l2, l3;
    float s, p;
    scanf("%c%c%c", &l1, &l2, &l3);
    p = (a + b + c) / 2.0;
    s = sqrt(p * (p - a) * (p - b) * (p - c));
    printf("%f", s);
}
int main()
{
    int s, l1;
    scanf("%s%s", &s, &l1);
    int l2;
    l2 = sqrt((s * 2 / l1) * (s * 2 / l1) + li * li);
}
int main()
{
    int a, b;
    scanf("%c%c", &a, &b);
    if (a % 2 == 1 && b % 2 == 1)
    {
        return a + b;
    }
    else if (a % 2 == 0 && b % 2 == 0)
    {
        return a * b;
    }
    else
    {
        return a - b > 0 ? a - b : b - a;
    }
}
int main()
{
    float sum = 0;
    int t = 1;
    for (int i = 1; i <= 100; i++, t = -t)
    {
        sum + = 1 / i * t;
    }
    return sum;
}
int main()
{
    float sum = 0;
    for (int i = 1; i <= 100; i++)
    {
        sum += i / (i + 1);
    }
    printf('%f', sum + 1);
}
int main()
{
    int sum = 0;
    for (int i = 100; i <= 300; i++)
    {
        if (i % 3 && i % 5 && i % 7)
        {
            sum += i;
        }
    }
}
// 水仙花数
int main()
{
    int n, a, b, c;
    for (n = 100; n < 1000; n++)
    {
        a = n % 10;
        b = n / 10 % 10;
        c = n % 100;
        if (n = a * a * a + b * b * b + c * c * c)
        {
            printf("%d\n", n);
        }
    }
}
int main()
{
    int i;
    int number = 0;
    int zm = 0;
    int zf = 0;
    char c;
    for (i = 0; i < 80; i++)
    {
        c = getchar();
        if (c <= 'Z' && c >= 'A' || c <= 'a' && c >= 'Z')
        {
            zm++;
        }
        else if (c >= '0' && c <= '9')
        {
            number++;
        }
        else
        {
            zf++;
        }
    }
}
int main()
{
    int a[10], k = 0, i;

    for (i = 0; i < 10; i++)
        scanf("%d", &a[i]);
    for (i = 1; i < 10; i++)
        if (a[i] < a[k])
            k = i;
    printf("max=%d,k=%d", a[k], k);
}
int main()
{
    int a[10], b[10], t;
    for (int i = 0; i < 10; i++)
    {
        scanf("%d", &a[i]);
    }
    for (int i = 0; i < 5; i++)
    {
        t = a[i];
        a[i] = a[9 - i];
        a[9 - i] = t;
    }
}
int main()
{
    int a[10][10], get;
    for (int i = 0; i < 10; i++)
    {
        for (int j = 0; j < 10; j++)
        {
            scanf("%d", &a[i][j]);
        }
    }
    for (int i = 0; i < 10; i++)
    {
        for (int j = 0; j < 10; j++)
        {
            scanf("%d", &a[i][j]);
        }
    }
}
int man()
{
    char c[100];
    scanf("%c", &c);
    int i = 0;
    gets(a);
    while (a[i] != '\0')
    {
        i++;
    }
    printf("%d", i);
}
int main()
{
    char c[100];
    int i = 0;
    int zm = 0, sz = 0, zf = 0;
    while (a[i] != "\0")
    {
        if (a[i] > 'a' && a[i] <= 'z' || a[i] > 'A' && a[i] <= 'Z')
        {
            am++;
        }
        else if (a[i] > '0' && a[i] <= '9')
        {
            sz++;
        }
        else
        {
            zf++;
        }
    }
    i += ;
    printf("%d%d%d", zm, sm, zf);
}

int main()
{
    int a, b, c;
    scanf("%d%d%d", &a, &b, &c);
    printf("%d", max(1, max(2, 3)));
}
int max(int x, int y)
{
    return x > y ? x : y;
}

int main()
{
    char c[100];
    int i = 0;
    int sum = 0;
    gets(a);
    while (c[i] != '\0')
    {
        if (c[i] >= '0' && c[i] <= '9')
        {
            printf("%c", c[i]);
            if (c[i + 1] != '\0')
            {
                printf("+");
            }
            sum += c[i];
        }
        i++;
    }
    printf("=%d", sum);
}

int main()
{
    char a[100], *p = a;
    gets(a);
    while (*p)
        p++;
    while (--p >= a)
    {
        putchar(*p);
        putchar('\n');
    }
}

int main()
{
    int h, m, n;
    int t = 0;
    int s = 0;
    scanf("%d,%d,%d", &h, &m, &n);
    while (t * (m - n) <= h)
    {
        s += m;
        if (s >= h)
            break;
        s -= n;
    }
    printf("day=%d", t);
}